This invention relates to a medical gas or vacuum regulator used to provide gas or vacuum for patient use, and, more specifically, it relates to an improved selector valve that has a plurality of positions with means to hold the valve in each of such positions and which overall is made up of fewer parts involving less tedious assembly than prior selector valves.
In medical applications, vacuum is often used for various suctioning functions carried out on a patient to remove fluids and in hospitals, there typically is provided, a central vacuum system where the various pieces of suction equipment may be connected by plug in recepticles, to that system.
In order to control the level of vacuum, modules are generally utilized and which may connect directly into the vacuum system and which include a pressure regulator, a gauge to determine the vacuum level and a selector valve that allows the operator to select either unregulated vacuum directly from the hospital central system or, alternatively, vacuum that has been regulated by use of the regulator incorporated into the module.
Due to increasing competition in the production of such modules, it is becoming significant to reduce, to the extent possible, the cost of such modules in order to maintain competitiveness. Since one of the main components of such modules is the multiposition selector valve, reduction in its cost is important, both from a materials as well as an assembly time standpoint.
Present selector valves used for the aforementioned purpose generally have a number of parts and require certain tedious assembly. As an example, one device currently on the market includes a rotatable valve where the valve surfaces require critical flatness to the extent that one of the rotating surfaces of the moving valve member must be lapped surface steel, thus the parts are fairly expensive.
In addition, it is desirable that a position latch be provided in each position so that the operator knows when the selector valve is fully in one of the selected positions, thus a spring and detent system is used to give the positive feel to the valve. Assembly of spring and detent types of positive valve engagement are, however, tedious to assemble since the assembler must manually align a tiny spring and spring follower in order to complete the unit.